1. Field of the Invention
The present invention relates to a waterproof connector suited to use in, for example, electric wiring in automobile.
2. Description of the Prior Arts
Hitherto, the waterproof seal in waterproof connectors for electric wiring has been achieved by an endless seal ring having a circular cross-section and made of an elastic material such as rubber, tightly clamped between the peripheral surfaces of the male and female connector housings at the juncture therebetween, because this type of sealing ring offers the following advantage. Namely, since this seal ring has a circular cross-section, this seal ring can make a close fit at its inner and outer peripheral surfaces to the outer peripheral surface of the male connector housing and the inner peripheral surface of the female connector housing respectively and, even if the connector housings are moved axially relatively to each other to cause a twisting deformation of the sealing ring, the sealing ring maintains close contact with the outer peripheral surface of the male connector housing and the inner peripheral surface of the female connector housing to keep good water-tightness of the seal.
A known waterproof connector of the kind described has an annular groove formed in the outer peripheral surface of the male connector housing and receiving the seal ring, the male connector being received by a hollow cylindrical portion of the female connector housing in such a manner that the seal ring makes a close contact at its outer peripheral surface with the inner peripheral surface of the cylindrical portion of the female connector housing. This known waterproof connector, however, suffers the following disadvantage. Namely, since the seal ring fitted around the outer peripheral surface of the male connector housing is exposed to the outside before fitting the male connector housing into the female connector housing, the seal ring is liable to be damaged when the connector is used, for example, in the assembling of wire harness of an automobile or the like and when the wire harnesses employing the connectors are mounted on the automobile. Clearly, any damage in the surface of the seal ring seriously deteriorates the water-tightness of the seal formed by the seal ring.
A waterproof connector, improved to obviate the above-described problem of the prior art, is disclosed in Japanese Utility Model Laid-Open No. 46827/1980 laid open to public inspection on Mar. 27, 1980. In this improved waterproof connector, the seal ring is fitted in the hollow cylindrical portion of the female connector housing and is retained in the hollow cylindrical portion by means of a retainer ring inserted into the cylindrical portion. The male and female connector housings are adapted to be fitted to each other in this state. It will be seen that this arrangement obviates the problem of the prior art mentioned above because the seal ring is concealed by the hollow cylindrical portion of the connector housing and does not appear to the outside.
This improved waterproof connector, however, imposes the following new problem. Namely, when the male and female connector housings are fitted to each other, the male connector housing is locked by the retainer ring and is fixed to the female connector housing through the lock provided by the retainer ring. Since the male and female connector housings are fixed to each other indirectly through the retainer ring, the fit between two connector housings tends to become loose. Another problem is that, when the male and female connector housings are separated from each other, the retainer ring is withdrawn from the female connector housing following the male connector housing and this withdrawal of the retainer ring is often accompanied by the withdrawal of the seal ring undesirably.